Tenderness is a major quality attribute that affects market price and consumer acceptance of meat products. The lack of consistency of beef tenderness is a major reason for decreased beef consumption in the U.S. There are several methods for improving meat tenderness, including mechanical tenderization, elevated temperature storage, calcium chloride injection, electrical stimulation, muscle stretching, shock-wave pressure, dry and wet aging, and enzymatic treatment. One of the most widely used is treatment with an enzyme, such as, e.g., papain, bromelain, or ficin. These enzymes, however, have very broad specificities and therefore hydrolyze indiscriminately the major meat proteins (connective tissue/collagen and myofibrillar proteins) resulting in an over-tenderized (i.e., mushy) product. Furthermore, papain, which is the most widely used, is relatively heat-stable, allowing uncontrolled texture deterioration during and after cooking.
Thus, there is a need in the art for meat tenderization methods employing enzymes which, unlike papain, have narrow substrate specificity; express self-limiting hydrolysis of meat proteins; hydrolyze either of the two major meat protein components, but not both; are thermolabile and thereby readily inactivated at cooking temperatures; and have no adverse effect on flavor.